Speech recognition for use in repertory dialing of telephone numbers is a well-known concept. See Rabiner et al., "A Voice Controlled Repertory Dialer System," Vol. 59, No. 7, The Bell System Technical Journal, p. 1153 (1980). The basic notion is that a speech recognition system may be trained to recognize, among other things, names of people that a telephone user may wish to "dial." The recognizer has a memory which includes speech recognition models (such as, for example, conventional hidden Markov models (HMMs) or templates) of the names of persons which are likely to be spoken for dialing. This memory is referred to as the recognizer "vocabulary." Associated with each model is a telephone number to be dialed. When a user speaks a name in the vocabulary, the recognizer recognizes the name and causes an automatic dialer to generate signals, such as conventional DTMF signals, which initiate a telephone call to the person whose name was recognized.
Speech recognition for automatic repertory dialing has been applied in both the telephone and telephone network contexts. In the telephone context, the recognizer/dialer system replaces the use of the DTMF keypad for those names in the vocabulary. See, e.g., U.S. Pat. No. Re. 32,012, entitled "Spoken Word Controlled Automatic Dialer," which is incorporated by reference as if set forth herein. Such a telephone can be used with a completely conventional public switched telephone network, such as the AT&T network, which receives DTMF signals and establishes a connection between the calling and called parties. The network makes no distinction between DTMF tones generated by a person (as in conventional manual dialing) and those generated automatically as a result of speech recognition.
In the network context, a special network node (or switch) is deployed in the telephone network for performing the functions of speech recognition and control signal generation. A network service customer (subscriber) accesses the node either at dial tone or as a result of dialing a special node access number, such as *96 or a "1-800" number. The subscriber speaks the name he desires to call and the node performs the recognition task. In response to recognizing a spoken name, control signals are generated by the node to complete the call to the called party.
In both the telephone and telephone network contexts, the user must supply the automatic dialer with the list of names and corresponding numbers which the user (or subscriber) wishes to be able to "dial" by voice. This supply process is cumbersome and requires the user to determine for himself the list of names and numbers which would be most convenient to include in his repertory dialing vocabulary.